In the prior art, there is known a printer apparatus configured to print predetermined information on a print sheet such as a label or a tag and discharge the printed sheet. In addition, a labeling machine capable of bonding a print sheet (such as a label) subjected to printing to a corrugated fiberboard or other labeling objects has been also developed (for example, see JP 4666598 B).
In such a printer apparatus, various printing types such as thermal transfer printing, (heat sensitive) color developing printing, inkjet printing, and electrostatic printing are employed. In the printer apparatus, it is required to perform inspection or maintenance works for various mechanisms or parts such as a control board or a driving gearbox.